Re: [PATCH v3 1/7] perf: build: Setup PKG_CONFIG_LIBDIR for cross compilation

[Namhyung Kim <namhyung@kernel.org>]

Hi Leo,

On Sat, Jul 06, 2024 at 07:29:06PM +0100, Leo Yan wrote:
> On recent Linux distros like Ubuntu Noble and Debian Bookworm, the
> 'pkg-config-aarch64-linux-gnu' package is missing. As a result, the
> aarch64-linux-gnu-pkg-config command is not available, which causes
> build failures.
> 
> When a build passes the environment variables PKG_CONFIG_LIBDIR or
> PKG_CONFIG_PATH, like a user uses make command or a build system
> (like Yocto, Buildroot, etc) prepares the variables and passes to the
> Perf's Makefile, the commit keeps these variables for package
> configuration. Otherwise, this commit sets the PKG_CONFIG_LIBDIR
> variable to use the Multiarch libs for the cross compilation.
> 
> Signed-off-by: Leo Yan <leo.yan@arm.com>
> ---
>  tools/build/feature/Makefile | 26 +++++++++++++++++++++++++-
>  tools/perf/Makefile.perf     | 26 +++++++++++++++++++++++++-
>  2 files changed, 50 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
> index ed54cef450f5..65fd2b2cfacb 100644
> --- a/tools/build/feature/Makefile
> +++ b/tools/build/feature/Makefile
> @@ -82,7 +82,31 @@ FILES=                                          \
>  
>  FILES := $(addprefix $(OUTPUT),$(FILES))
>  
> -PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
> +# Some distros provide the command $(CROSS_COMPILE)pkg-config for
> +# searching packges installed with Multiarch. Use it for cross
> +# compilation if it is existed.
> +ifneq (, $(shell which $(CROSS_COMPILE)pkg-config))
> +  PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
> +else
> +  PKG_CONFIG ?= pkg-config
> +
> +  # PKG_CONFIG_PATH or PKG_CONFIG_LIBDIR is required for the cross

And PKG_CONFIG_SYSROOT_DIR too.


> +  # compilation. If both is not set, try to set the lib paths installed
> +  # by multiarch.
> +  ifdef CROSS_COMPILE
> +    ifeq ($(PKG_CONFIG_LIBDIR)$(PKG_CONFIG_PATH)$(PKG_CONFIG_SYSROOT_DIR),)
> +      CROSS_ARCH = $(shell $(CC) -dumpmachine)
> +      PKG_CONFIG_LIBDIR := /usr/local/$(CROSS_ARCH)/lib/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/local/lib/$(CROSS_ARCH)/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/lib/$(CROSS_ARCH)/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/local/share/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/share/pkgconfig/
> +      export PKG_CONFIG_LIBDIR
> +      $(warning Missing PKG_CONFIG_LIBDIR and PKG_CONFIG_PATH for cross compilation,)

Probably you need to add it here too.

> +      $(warning set PKG_CONFIG_LIBDIR=$(PKG_CONFIG_LIBDIR) for building with Multiarch libs.)

I guess the message would get too long.  Maybe it's ok to hide the
actual value..

In addition, I think this message will be displayed multiple times -
once here and later in Makefile.perf.  Maybe we can show it once in
the latter only?

Thanks,
Namhyung


> +    endif
> +  endif
> +endif
>  
>  all: $(FILES)
>  
> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> index 5c35c0d89306..270490be0a1a 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -193,7 +193,31 @@ HOSTLD  ?= ld
>  HOSTAR  ?= ar
>  CLANG   ?= clang
>  
> -PKG_CONFIG = $(CROSS_COMPILE)pkg-config
> +# Some distros provide the command $(CROSS_COMPILE)pkg-config for
> +# searching packges installed with Multiarch. Use it for cross
> +# compilation if it is existed.
> +ifneq (, $(shell which $(CROSS_COMPILE)pkg-config))
> +  PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
> +else
> +  PKG_CONFIG ?= pkg-config
> +
> +  # PKG_CONFIG_PATH or PKG_CONFIG_LIBDIR is required for the cross
> +  # compilation. If both is not set, try to set the lib paths installed
> +  # by multiarch.
> +  ifdef CROSS_COMPILE
> +    ifeq ($(PKG_CONFIG_LIBDIR)$(PKG_CONFIG_PATH)$(PKG_CONFIG_SYSROOT_DIR),)
> +      CROSS_ARCH = $(shell $(CC) -dumpmachine)
> +      PKG_CONFIG_LIBDIR := /usr/local/$(CROSS_ARCH)/lib/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/local/lib/$(CROSS_ARCH)/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/lib/$(CROSS_ARCH)/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/local/share/pkgconfig/
> +      PKG_CONFIG_LIBDIR := $(PKG_CONFIG_LIBDIR):/usr/share/pkgconfig/
> +      export PKG_CONFIG_LIBDIR
> +      $(warning Missing PKG_CONFIG_LIBDIR and PKG_CONFIG_PATH for cross compilation,)
> +      $(warning set PKG_CONFIG_LIBDIR to $(PKG_CONFIG_LIBDIR) for using libs with Multiarch.)
> +    endif
> +  endif
> +endif
>  
>  RM      = rm -f
>  LN      = ln -f
> -- 
> 2.34.1
>